<!-- <!doctype html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>选择器</title>
	<style type="text/css">
	*{
		font-size: 20px;
	}
    #qwe1{
    	color: red;
    }
    .qwe2{
    	color: blue;
    }
    span,a{color: green;

    }
    p i{
    	color: yellow;
    }
    #qwe1:hover{
    	color: blue ;   
       }
	</style>
</head>
<body>
	<p id="qwe1">这个是一个p标签</p>
    <p class="qwe2">这个是一个p标签</p>
    <p class="qwe2">这个是一个p标签</p>
    <p class="qwe2">这个是一个p标签</p>
    <span>这是span标签</span>
    <span>这是span标签</span>
    <span>这是span标签</span>
    <a href="">这是a标签</a>
    <p>
    	<i>这是里面的i标签</i>
    </p>
    <i>这是外面的i标签</i>


    <p class="top">
    	<p class="top_mid">
    		<p class="top_menu">
    			
    		</p>
    	</p>
    </p>
</body>
</html> -->

<!doctype html>
<html lang="en">
<head>}
	<meta charset="UTF-8">
	<title>选择器</title>
	<style type="text/css">
    #qwe1{
    	color: blue;
    }
    .qwe2{
    	color: red;
    }
    span,a{
    	color: green;
    }
    p i{
    	color: yellow;
    }
    .qwe2:hover{
    	color: blue;
    }
	</style>
</head>
<body>
	<p id="qwe1">这是p标签</p>
	<p class="qwe2">这是p标签</p>
	<p class="qwe2">这是p标签</p>
	<p>这是p标签</p>
	<span>这是span标签</span>
	<span>这是span标签</span>
	<span>这是span标签</span>
	<a href="">这是a标签</a>
	<p>
		<i>这是里面的i标签</i>
	</p>
	<i>这是外面的i标签</i>

	<p class="top">
		<p class="top_mid">
			<p class="top_menu">
				
			</p>
		</p>
	</p>
</body>
</html>